Captain Gabriel Stone was a Resistance serving in 2027. While on a mission, Stone, who was a Squad leader, was captured by Skynet and presumed to be dead. However, it turns out that Stone had actually led his team into a trap and became a defector to Skynet's cause. Willingly allowing himself to become one of Skynet's experiments, Stone was transformed into a Skynet Initiate. Having become an agent of Skynet, Stone made contact with his younger brother, Alexander and convinced his brother to also defect.
During the raid on Cheyenne Mountain, Gabriel Stone and his brother, who had became an Initiate as well, fought alongside Skynet against the Resistance. Both escaped from Cheyenne Mountain following the destruction of Skynet's central processor.
- The ending of the game The Terminator: Dawn of Fate implies that Gabriel and his brother Alexander have turned their backs on Skynet and its objectives as his brother tells him that both of their enemies have been crippled.